6/3-(4-Chlorophenyl)-s-triazolo[3, 4-b][1, 3, 4]thiadiazoles (2a-e) and (5a-e) were synthesized respectively by intermolecular cyclization of 5-aryl / 4-chlorop
This study compares the trends and frequencies of drought between central North China(CNC) and(SSA) for the periods 1901–2010 and 1951–2010. The Standardized